This invention relates to a combination of a hinge for doors or wings and a damping device. More specifically, the hinge is designed to connect the door of an electrical household appliance, such as a refrigerator, to a respective mounting frame.
In customary refrigerators, which this specification specifically refers to but without thereby restricting the scope of the invention, the hinges normally comprise two fastening arms mounted on the outside, one on the door and the other on the refrigerator frame. The two fastening arms are hinged to each other directly or, more usually, through one or more interposed levers.
The hinges often have a built-in damping device designed to eliminate or at least significantly reduce the stresses and noise produced when the door is banged or slammed shut.
A solution of this kind is disclosed in patent application EP 1884614 A2, where a piston and cylinder unit is hinged, on one side, to the part of the hinge that is fixed to the frame and, on the other side, to the door of a refrigerator.
The damping device described in patent application EP 1884614 A2 is mounted on the outside of the hinge, making it not only dangerous but also unattractive since it is clearly in view when the door is open.
Another solution is known from patent application WO 2008/119647 A1. In that case, the piston and cylinder unit is mounted on the inside of the hinge but this makes the hinge mechanically complex and relatively expensive to manufacture.
In other prior art solutions, generally speaking, the damping device is applied as a separate component to a hinge of a door, wing or the like.
For example, German patent DE 19522254 C2 discloses a cylinder and piston unit mounted on a door frame in such a way that, when the door is opened, the free end of the piston is stretched forward to an extended position. That way, before the door reaches the closed position, it comes into contact with the free end of the piston, which compresses the air inside the cylinder, thereby slowing down the door.
This solution, too, is not free of disadvantages, however. In effect, the thrust which the piston receives from the door is not perfectly axial, producing stress on the damping device which, in the long run, may lead to faulty sliding of the piston in the cylinder. Moreover, the free end of the piston protrudes from a zone of the frame where it may easily and dangerously interfere with the movements of the user.